abdominal pregnancy, extrauterine pregnancy implanted outside the uterus exclusive of implantation on or in the fallopian tube or ovary. Uncommon, with diagnosis by exclusion and confirmation by ultrasound or MRI. Depending on gestational age and location of implantation, therapy ranges from medical (methotrexate) to surgical, the latter often difficult, depending on the implantation site and the degree of vascularity in the implantation. Often the gestation is removed at surgery, but the placenta is left in situ to be treated by methotrexate. It is one of the rare causes of maternal death, almost always due to delayed diagnosis and hemorrhage. Formerly called abdominocyesis.
